Heretofore, high pressure fluid blast guns have presented handling problems to the operator due to the significant forces attendant on gun operation. The reaction forces produced by high pressure fluid tends to make the guns difficult and tiring to handle. Typically an operator has to stand in a crouched or semi-crouched position to brace himself in order to handle the reaction forces produced in the gun by the high pressure fluid. Guns which have standard size and length components require the operators to adjust their posture to accommodate the guns, rather than having a gun brace which can be adjusted to fit the size of the operator. Also, attaching the inlet high pressure hose near the rear of the gun requires the operator to overcome the reaction forces of the gun merely to control it when it is manually operated. This typically requires the operator to use his body to hold the reaction force created by the fluid blaster.
It is an object of the present invention to provide a fluid blast gun that is ergonomically more effective in that it affords some latitude in the length of the shoulder brace to accommodate operators of different sizes.
It is also an object of the present invention to provide a hydroblast gun which has a "Y" fitting on the gun barrel for connecting the high pressure inlet hose forward of the control mechanism to take advantage of the reaction force in the high pressure hose that tends to counteract the thrust from high pressure fluid being discharged from the end of the barrel. Since the high pressure fluid in the high pressure hose tends to straighten the hose, the "Y" fitting in the barrel causes the straightening hose to tend to force the gun forward rather than backward and thereby counteract the end thrust load that is imposed on the operator.
A further object is to provide a high pressure blast gun with a floating valve seat and piston which enables the piston and seat to align perfectly when actuated by the cam action of the gun trigger.
A further object is to provide a high pressure blast gun with a reversible piston and a reversible floating seat which can be aligned with the piston and which can be easily removed from the gun by the operator to enable him to conveniently reverse the piston or seat should they become worn and thus minimize down time required for gun maintenance as well as reduce the cost of wear parts in the gun.
Another object of this invention is to provide a high pressure nozzle with a dump or diverter chamber which is attached to the high pressure piston chamber by means of a swivel mechanism that allows the dump chamber to which the dump hose is connected to be turned or swiveled so as to align the dump hose on either side of the operator.